import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 25397
 * Date: 2022-07-07
 * Time: 16:14
 */
public class DBUtil {
    private static final String URL="jdbc:mysql://127.0.0.1:3306/bbq?characterEncoding=utf8";
    private static final String USERNAME="root";
    private static final String PASSWORD="123456";

    private volatile static DataSource dataSource=null;

    private static DataSource getDataSource(){
       if(dataSource==null){
           synchronized (DBUtil.class){
               if (dataSource==null){
                   dataSource=new MysqlDataSource();
                   ((MysqlDataSource)dataSource).setURL(URL);
                   ((MysqlDataSource)dataSource).setUser(USERNAME);
                   ((MysqlDataSource)dataSource).setPassword(PASSWORD);
               }
           }
       }
        return dataSource;
    }

    public static Connection getConnection() throws SQLException{
        return getDataSource().getConnection();
    }

    public static void close(Connection connection, PreparedStatement statement, ResultSet resultSet){
        if(resultSet!=null){
            try {
                resultSet.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if(statement!=null){
            try {
                statement.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if (connection!=null){
            try {
                connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}
